Double-acting air pump



June 22 1926.

1,589,389 H. C. HEADSTREAM v DOUBLE ACTING AIR PUMP Filed April 16, 1925 "A Wa Patented .lune 22, 1926.

V, UNITED STATES HERBERT o. HEADSTREAM, F RIB LAKE, WISCONSIN.

DOUBLE-ACTING AIR PUMP.

Application filed April 16, 1925. SeralNo. 23,495.

This invention relates to a pump, and particularly a double-acting pump adapted' to pump and compress fluids, the device being particularly designed for compressing air.

It is an object of this invention to provide a simple and efficient double-acting pump comprising two sets of cylinders, one set of which is valve equipped and the other of which is not valve-equipped.

It is a further object of the invention to provide such a pump, as set forth in the preceding paragraph, comprising two pairs of cylinders, the cylinders of each pair being axially alined and having pistons there1n connected by a common piston rod, said piston rods, in turn, being connected to an operating means.

It is another object of the invention to provide a pump comprising spaced chambers in which the fluid is compressed, which chambers are connected by a suitable valvecontrolled conduit, one of said chambers having an outlet conduit connected thereto, said pump comprising two sets of cylinders, one set of which communicates with one vchamber and the other set of which communicates with the other chamber. ,Y

lt is a still further objectof the invention to provide such pump as set forth comprising a simple Vand efficient frame conveniently arranged for carrying all of said parts.

These and other objects and advantages of the invention will be fully set forth in the following description made in connection with the accompanying drawings in which like reference characters refer to thev same parts throughout the different views, and in which- Fig. 1 is a central vertical section through the pump; f

Fig. 2 is a horizontal section taken on the line 2-2 of F ig.r1;

Fig. 3 is a horizontal the line 3 8 of Fig. 1;

Fig. 4 is a horizontal section taken onthe line ,L-f of Fig. 1; j

Fig. 5 is a horizontal section taken on the line 5 5 of Fig. 1, said sections being taken as indicated by the arrows; and` Fig. 6 is a view in vertical section illustrating the structure of valve used.

Referring to the drawings, a pump is shown-comprising a frame formed of a lower portion 7, intermediate portion -8, an upper portion 9,v and `a Ytop port-ion` or cover-10.

. section taken on The portion '7 is ofv generalelliptical shape,

as shown in Figs. 4 and 5 and has formed therein cylinders 11 and 12, said cylinders being disposed at opposite sides of said frame portion and transversely alined or having their top and bottom portions, respectively at the same level. The cylinders 11 and 12 haveinlet valves 13 at their lower ends, and while these valves may be of any suitable type permitting air to move into the cylinders but preventing air leaving the same the construction is substantially shown in Fig. 6. In said ligure, the valve is shown comprising a valve 13a adapted to contact the seat 13b to -close the valve but being movable from said seat against the spring 13,

a one-Wayk check valve being thus provided. i

The space inthe frame section between the cylinders llrand 12 forms a storage chamher for air and said space communicates with the bottom ofcylinders 11 and 12 through the outlet valves 14, said valves V14V permitting the exit of air from said cylinders but preventing air entering the same. The frame section 7 has a circular flange 7a at its upper end contacting a similar and equal size flange 8l at the bottom of the central section 8, said Hanges being tightly pulled together by headed andnutted bolts 15. The section 8' has a circular flange 8hv at its upper end which, in turn, is bolted to a ,similar and equal sized lflange 9a at the lower end of the upper section 9 by similar headed and nutted bolts 15. The upper section 9 is substantially cylindrical in shape, as shown in Fig. 2, and also has at opposite sides thereof cylinders 16 and 17, The space between the cylinders 16 and 17 also forms a storage space for air, said space having the bottoni or diaphragm 9b and said space communicating with the upper ends of cylinders 16 and 17. The cylinders 16 and 17 preferablyareA of larger diameter than the cylinders 11 and 12. v

It will be notedthat the lower ends of cylinders 16 and 17 ,are open and that the upper ends of the cylinders 11 and 12' are open. The cylinder 16 is axially alined with the cylinder 11 and the cylinder' 17 is axiallyyalined with the cylinder 12. vAll of said cylinders are equipped with pistons, the cylinders '11 and .12 having the pistons 16 and 19, respectively, therein while the cylinders 16 and 17 have pistons 20 and 22,

respectively, therein. The pistons 19 and 22 arekconnected by a common piston rod 23.".ll7hile the pistons 18 and 20 are, likello Wise, connected by a common piston rod 211, which rods pass through the centralframe portion 8. r'he piston rocs 23 and 24. are adapted to be operated` by a common operating member andl 1While 'they may-'be va riously formed, in the embodiment o f the invention illustrated, said piston rods are formed as oppositely directed? racks and a gear 25 is provided, the teeth of which mesh with the t-eeth of said racks. The frame portionS has a central rib or member 8C eX- tending thereacross having spaced intermediate portions vrprovided with oppositely.` e5;- tending central bosses 3Q-Which" are bored to receive a shaft 'comprising "a headed stud 2G Vjournaled therein andheld in lplace by having one Yend threaded and provided With a suitable nut. Said studv has a central portionA of angular'shape in cross sectionl on Which the gear 25 is mounted. The'gear'25 and the flattenedfporti'onsof piston rod 23 and 241 forming therack move' through the member 8"Which thus forms vva guiding means' therefor." The shaft o'r stud 26 is adapted to be oscillated and While this may be done by any suitable means', in the einbodi'ment `of the invention illustrated, a lever 27 is shown as connectedv to stud- 26 by a suitable set screw 27 t, which lever projects through an openingin one side of the frame portion 8. The'chamber in the frame portion: 7 and the chamber in the upper portion'S) are connected'by a pipe or conduit 28 having disposed therein a valve 29 and anV outlet pipeI 30 communicating. with pipe 28 through a suitable T connection is provided also equipped with a valve 31. The top, section 10 is of semi-spherical f ormation having a circular flange boltedto'an upper flange '9c on the Vsection 9by headed and nuttedbolts '32,' 'said top section 10 forming theV top of the chamber in section 9. A gasket (not shown) preferablyftvill be provided between'sectiion 10 and flange 9 to provide an air-tight joint.

Then the pump is to be operated for compressing fluid, the valve 29 Will be opened and' valve 31 closed.l Lever 27 will then be oscillated by any suitable means and piston rods 23 and 24 Will then be reciprocated in opposite directions. As the pistons 18 and 19 are raised, air is drawn into the cylinders 11 or 12, respectively, through the inlet valvesf13 and then when pistons 18 and` 19 are depressed, this air is compressed andforcedvthrough the 'outlet`valves 14 into theI chamber between cylinders 11 and 12. Air is thuscompressed andforced into said chamber andthe'l pressure in said-chamber equalizes through the pipe 28 with theI upper chamber between cylinders 16 and 17T.

During this operation off the pump it willV be noted Lthattlie V'pistons 20 and' 22 form guide meansjfor' the'v pistons 18V and :'19, re spective'lyfand'- for the piston rods y24C and Said pistons and rods are thus kept accurately in proper alinement. There will be no additional power required to raise the piston 2Q or 22asgthe pressure in the chamber communicating With said pistons Will tend to force one piston down at the same pressure required to lift the other piston. After a sufficient pressure of air has been attained in the storage chambers the valve 29 may be closed vand the compressed air supplied to the desired apparatus through the pipe 30 by opening valve 31. rllhe aii` can be supplied from both chambers, if de sired, by allowing valve 29 to remain open orthe pressure can be raised in the loiver chamber after some of the airy has been used by opening'valve 29.

F rom the above description it is seen that applicant has provided a simple, compact and eiicient structure of pump or compressor. The pistons 18 and 19 are effectively "operated by a common operative member 25 `and the pump is quite rapid in securing the desired pressure of air. rlhe parts of the device are comparatively few and simple and` easily made and such parts are quite easily assembled. By having the chambers between cylinders 11 and 12 and at the upper end of cylinders 1G and 17, the structure is greatly simplified and the chambers and'cylinders are provided with a minimum ofA frame structure. By'having the cylinders 16 and 17 opening direct-ly'into the chamber at the upper end thereof, conduits'c'onnecting this storage space with the cylinders are eliminated, as is also the necessity' of cylinder heads. The arrangement of 'pairs of cylinders in alinement, With the common parts operatingy them also results in a machine functioning and accomplishing the desiredfresult with a very small number of parts; A very compact and efficient machine is thus provided.

It will, of course, be understod, that various changes may be made in the form, details, arrangement and proportions of the parts Without departing` from the scope of applicants invention which, generally stated, consists in a device capable of carrying out the object above set forth and in the novel parts and combinationsv of parts disclosed and set forth in the appended claims.

VVhatis claimed is:

1. A'double-acting pump for compressing fluids having in combination, a pair of parallel cylinders, a chamber into which said cylinders discharge through valve controlled passages, inlet valves for said cylinders, a pair of parallel cylinders spaced from and respectively axially alined With said first mentioned cylinders, a chamber communicating with the ends of said last mentioned cylinders, pistons in all of said cylinders` a pair of'piston rods respectively .connecting the pistonsin said axially alined cylinders,

a movable member operatively connected to said piston rods for moving the same simultaneously in opposite directions and a conduit connecting said chambers.

2. The structure set forth in claim 1, a valve in said conduit for opening and closing the same, and a valve-controlled conduit communicating with said first mentioned chamber.

3. A double-acting pump for fluids having in combination, a frame, a chamber at the bottom thereof, a pair of cylinders having their upper and lower ends, respectively in the same horizontal plane at each side of said chamber, said cylinders having discharge ports at their lower ends opening into said chamber, inlet ports in said'cylin; ders at their lower ends, the upper ends of said cylindersbeing open, said frame having a chamber at its upper end, a pair of parallel cylinders at the sides of said last mentioned chamber having open Lipper ends at the same level communicating with said last mentioned chamber and having open lower ends at the same level, said last mentioned cylinders each alining axially with one of said first mentioned cylinders, pistons in all of said cylinders, a connecting rod connecting the pistons in each pair of axially alined cylinders, a valve controlled conduit connecting said chambers, an operating shaft journaled in said frame between said chambers and a member on said shaft engaging both 'of said connecting rods to move the same in oppositedirections, and means for oscillating said shaft.

4. A double-acting pump for compressing fluids having in combination, a pair of parallel cylinders, a chamber into which said cylinders discharge through valve controlled passages, inlet valves for said cylinders, a pair of parallel cylinders spaced from and respectively axially alined with said first mentioned cylinders, a chamber communicating with the ends of said last mentioned cylinders, pistons in all of said cylinders, a pair of piston rods respectively connecting the pistons in said axially alined cylinders, ka frame carrying all of said cylinders including a member disposed substantially centrally between said pairs of parallel cylinders and having a rectangular slot therein., a pair of oppositely facing racks in the ends yof said slot, a gear disposed in said slot meshing with both racks, a shaft carrying said gear journaled in said member, and means for turning said shaft and gear.

5. A double-acting pump for fluids having in combination, a pair of parallel cylinders having inlet and outlet valves at their lower ends and being open at their upper ends, a chamber into which said cylinders discharge, a pair of parallel cylinders having open upper and lower ends spaced from said first mentioned cylinders, each of said last mentioned cylinders being axially alined with one of said first mentioned cylinders, a closed chamber with which the upper ends of said last mentioned cylinders communi-A cate, pistons in all of said cylinders, a piston rod connecting the pistons in each pair of axially alined cylinders, a conduit connecting said chambers, a valve-controlled outlet conduit for said first mentioned chamber, and means for reciprocating said piston rods simultaneously in opposite directions.

6. A double-acting pump having in combination, a frame comprising a lower section having parallel cylinders at opposite sides thereof, inlet valves at the lower ends of said cylinders, respectively, outlet valves at the lowerends of said cylinders, said frame forming a chamber between said cylinders with which said outlet valves-eomn'iunicate, the upper ends of said cylinders being open, said frame comprising an upper portion having at opposite sides thereof parallel cylinders, each of which is axially alined with one of said first mentioned cylinders, said last mentioned cylinders being open at both ends and said upper Vportion of said frame forming a chamber with which the upper ends of said cylinders communicate, said frame having an intermediate portion bolted respectively to said lower and upper portions, a shaft journaled in said intermediate portion, a gear mounted on said shaft, pistons in all of said cylinders, a piston rod connecting the pistons in each pair of axially alined cylinders, said piston rods passing through said central frame portion and being formed with rack teeth on their adjacent sides, said teeth meshing with the teeth ofsaid gear, means for oscillating said gear, and a conduit connecting said chambers.

In testimony whereof I affix my signature.

HERBERT C. HEADSTREAM. 

